I have to say it is quite ironic that I am writing this at 2:45 in the morning, but I've decided to delve into the question of why we need sleep in hopes of successfully persuading myself to take up science's advice and break my vicious cycle of sleeping at ungodly hours. But I choose to blame time difference for causing the late nights spent fruitfully scrolling on my phone I have succumbed to recently (or maybe I should really place the blame on my lack of self-discipline...) So of course, if I can't make myself revive that long-lost regular sleep schedule, science can, so I took to the computer and researched more about sleep, from why we need it to the science behind it.
Our bodies regulate sleep with our internal "body clocks", which operate on a 24-hour cycle (circadian rhythm). During the day, as energy is broken down, a substance called adenosine is produced in your brain which makes you progressively tired as time passes. At night, this substance is broken down during sleep.
Light also plays a part in regulating our sleep. A cluster of cells found in the hypothalamus in the brain (called the suprachiasmatic nucleus, quite a mouthful to say) processes signals from the light that hits our eyes (diagram below), and helps the body tell if it’s day or night. As natural light decreases, a hormone called melatonin is released which increases drowsiness. In response to the increase in light in the morning, your body releases cortisol, increasing alertness and energy, giving you that kick-start to the day.
One really important process that occurs during sleep is memory consolidation, namely the process that transforms newly-learnt information into long-term memory, kind of like your brain doing some admin stuff while you're asleep. This is exactly why late-night cramming sessions are so harmful and can actually be counter-effective: the brain needs to be given adequate "downtime". In order to retain the fascinating organic chemistry you've just studied, you need memory consolidation, so sleep really is your best friend when it comes to having a test the next day!
There was also a very interesting study into Platynereis dumerilii, a marine worm, that showed how sleep has evolved. In the dark, melatonin production is triggered which stops the beating of the little hairs on the surface of the worm, so they sink lower down in the waters. When day comes again, they start beating their little hairs and rise to the surface, ready to start their little worm days.
So all in all, sleep is so important to give our brains the rest it needs. Not enough sleep can impair the ability to concentrate, to think clearly or even to form memories. There are lots of simple techniques to establish a regular and sufficient sleep schedule, all of these which I will be following conscientiously: reducing caffeine consumption in the hours leading to bedtime, setting a bedtime and sticking by it, reducing distractions in your room - especially digital ones, as I often fall victim to the addictive feeling of scrolling through my Instagram feed- making your room nice and relaxing by lowering the lights, and the list goes on...
I've found learning about this topic through researching really fascinating, and I've heard that these books are amazing as well, so I'll definitely have a go at these soon. I hope you found this interesting and feel free to give any suggestions! :)
“Dreamland: Adventures in the Strange Science of Sleep” by David K. Randall
"The Universal Pastime: Sleep and Rest Explained" by Dr Richard Horner
"Why We Sleep: Unlocking the Power of Sleep and Dreams" by Matthew Walker
Sources I used: